How do you differentiate #f(x)=-5 xe^(x/cos x)# using the chain rule?
you'll need the product rule first of course so we can simplify by letting
then first we work the product rule so
and now for p', we know from the chain rule that
which means that
going back to Eqn A, and plugging this all back in, we then have
that could be tidied up maybe in some other way...
personally, i think it is helpful to look at logarithmic differentiation here
so we can instead say that
another way of looking at it
Taking the constant out,
Applying the product rule,
[i.e applying chain rule;